MODE-2323 Removed the proxy layer and delta write functionality in Schematic

ModeShape's is no longer using Infinispan in ways where these pieces of functionality are useful.
Removing them should simplify the logic to represent more of what we're actually doing. See MODE-2323 for details.
I'll try fixing the other issues (keeping the `PESSIMISTIC` requirement) and seeing how that works. If that does work fine, I'll update the PR and then look at putting in the `FAIL_SILENTLY` flag, putting back in this check, and reverting all of the Infinispan configurations that I changed from `OPTIMISTIC` to `PESSIMISTIC`.